Marketing your startup can get expensive and often the strategy you choose doesn't work as planned. How can you promote your products or services without spending a lot of money or time developing comprehensive marketing plans?

You've heard of the lean startup concept pioneered by entrepreneur Eric Ries and popularized over the years by professor Steve Blank. The lean startup approach, which favors experimentation over planning, offers a useful blueprint for developing a more efficient marketing strategy.

Here are three ways you can apply it to your business right now:

Test your marketing ideas in small batches.Instead of investing months to plan and research, lean startup encourages businesses to develop untested assumptions and quickly test those assumptions in the marketplace -- a concept that can easily be applied to your marketing efforts.

When you invest a majority of your marketing budget into developing strategies and tactics, you make a gamble that they will actually succeed. This is a sucker's bet because most marketing strategies fail.

Instead of developing big plans and investing the vast majority of your marketing budget in one or two initiatives, break your budget into smaller pieces and test a variety of ideas.

For example, do not commit to six-month marketing campaigns on Facebook and Twitter. Instead, dedicate a small budget to run two-week experiments. Pick a variety of images and develop four or five different ads. Within two weeks, look at the results to measure which ads send the most traffic to your site and which ads result in better conversions. Compare the traffic and conversions from Facebook and Twitter relative to the money you're spending. Is one network sending more customers? Do certain ads have higher click-through and conversion rates? Which ads perform best on both networks?

If your experiments fail, don't worry -- this is normal. At my company, 99 percent of the marketing tactics we try fail. Find several other channels -- pay-per click search-engine advertising or sponsoring a newsletter targeting potential customers, for example -- and run new two-week experiments.

You don't even have to run actual experiments on Facebook or Twitter. You can put together four or five ads and launch a survey on the crowdsourcing internet marketplace Amazon Mechanical Turk. Offer 500 people 10 cents each to answer a small number of questions about the ads. Refine the ads based on the answers and re-run the survey with a different batch of 500 people. By spending $100 before you run the ads, you'll be able to improve them and focus your marketing message.

Experimenting with different options will give you a better sense of how your prospective customers respond to your marketing so that you can focus your energy and budget on those channels and tactics that work best.

Leverage your customers' feedback.Marketing is typically one-way communication, but it doesn't have to be. Just as lean startup encourages businesses to listen to customer feedback in order to modify initial assumptions, businesses can easily find ways to leverage feedback from customers as they test marketing ideas.

After your two-week experiments on Twitter and Facebook end, for example, you'll have a group of customers who purchased your products or services that you can survey. Why were your messages effective to those customers? What made them click your ads and complete a purchase?

Ask your customers and try to offer incentives to encourage people to respond. At my company, for example, we often raffle a few $50 gift cards to survey participants. Call customers and conduct brief phone interviews, ask them on Twitter or Facebook, or develop a short online survey. Did they like the images in your ads? Did they respond to the content? Did they like the landing pages or did other factors lead them to make a purchase? What would have helped them purchase sooner?

Be prepared to change gears quickly.Once you've gathered this information, you can move into the third lean-startup stage, agile development: the process of improving your product or service in incremental ways in response to what you're hearing from customers.

If customers tell you certain images get them more interested in your products and services than others, find more of those images and re-test your assumptions. By doing this, you can adjust, refocus and find those marketing channels and messages that work best for your brand.

More from Entrepreneur

David provides constructive insight to help businesses focus on their company growth, build brand awareness and know when and how to raise money.